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  • 1
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 73 (1993), S. 2809-2815 
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Hydrogen nuclear magnetic resonance (NMR) was used to probe defect reactions in fused silica during 193 nm ultraviolet irradiation and thermal treatment. Hydrogen concentration and Carr–Purcell measurements indicate that the majority of hydrogen atoms are isolated and do not segregate or evolve from the fused silica during annealing or irradiation. Previously, NMR spin-lattice relaxation measurements have revealed that a small fraction of hydrogen in fused silica exists as centers that undergo molecular motion and are consumed during annealing. Here, a detailed analysis of the NMR spin-lattice relaxation behavior is used to support the identification of this center as a pair of adjacent silanol groups. These silanol pairs react during annealing to form a strained bond, thus increasing the susceptibility of fused silica to E' formation. Excimer laser irradiation, like thermal treatment, is shown to directly reduce the number of relaxation centers in the material. The measured dependence of spin-lattice relaxation as a function of irradiation for identically prepared samples is consistent with silanol pair center consumption by a two-photon process.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 56 (1990), S. 1072-1074 
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: A reaction, based on tungsten hexafluoride chemically reduced by silicon hydride vapors, has been developed for low-temperature laser deposition of high-purity tungsten. Compared to previous tungsten deposition methods, the new (pyrolytic) process requires very little thermal energy for initiation and propagation of the scanned reaction. WF6 and SiH4 (or Si2H6) mixtures have been optimized to yield tungsten interconnect lines with abrupt square cross section and conductivities of 12–25 μΩ cm. Impurity levels are below the detection limits of Auger spectroscopy. Lines 3–20 μm in width and 0.1–4 μm in thickness are written at scan speeds of ∼100 μm/s. Argon-ion laser powers (488 nm) are typically 30–60 mW, corresponding to reaction temperatures sufficiently low for direct writing on polyimide dielectrics.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 59 (1991), S. 1790-1792 
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Amorphous WO3 thin films have been deposited in a plasma-enhanced chemical vapor deposition system, and were patterned with a 193-nm excimer laser (one pulse, 10–25 mJ/cm2). Negative-tone, sub-0.5-μm lines and spaces were obtained following dry development in a low-power CF4 plasma. The mechanism for laser-induced etch selectivity was studied with angle-resolved x-ray photoelectron spectroscopy. It was inferred from the fluorine photoelectron spectra that the laser induces atomic rearrangements that impede the etch process initiated by fluorine-containing radicals. A possible interpretation is that the rearrangements, which may be partially thermally activated, reduce the volume of the microvoids present in WO3.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 60 (1992), S. 1667-1669 
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Nuclear magnetic resonance (NMR) was used to study hydrogen in fused silica for the first time. The 1H NMR spin-lattice relaxation time constant (T1) in synthetic fused silica was found to be strongly affected by thermal treatments, correlating with the concentration of E' centers produced during subsequent 193-nm excimer-laser irradiation. In addition, the relative proportion of the two components in the NMR spectrum were affected by thermal treatment, although no change in the total hydrogen content was observed. The broad NMR component, because of its linewidth and dependence upon thermal processing, is postulated to be a direct signature of the NMR relaxation centers. These results are interpreted within the framework of a model in which pairs of silanol groups are consumed during thermal treatment, forming a strained bond which is susceptible to E' center formation.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    Springer
    International journal of legal medicine 104 (1990), S. 49-53 
    ISSN: 1437-1596
    Schlagwort(e): Forensic neuropathology ; Craniocerebral injury ; Cortical artery lesion ; Biomechanism ; Forensische Neuropathologie ; Schädel-Hirn-Trauma ; Corticale Arterienverletzung ; Biomechanismus
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Rechtswissenschaft
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Ein 63jähriger Alkoholiker stürzt in betrunkenem Zustand im Treppenhaus. Auf der Rettungsteile ist der Mann schläfrig aber bei Bewußtsein; es werden neben der Alkoholisierung keine gravierenden Verletzungen festgestellt, Röntgenaufnahmen des Schädels verwackeln. Übernachtung in Polizeigewahrsam (GeSa), am nächsten Morgen zu Fuß nach Hause, dort über 2 Tage Eintrübung, Nausea, Erbrechen. $$2{\raise0.5ex\hbox{$\scriptstyle 1$}\kern-0.1em/\kern-0.15em\lower0.25ex\hbox{$\scriptstyle 2$}}$$ Tage nach dem Sturz von Ehefrau leblos im Bett aufgefunden. Obduktion: Oberfl. Schürfung Kopfhaut re. parietal, darunter Blutungen in der Galea und re. M. temp.; ausgedehntes Bruchsystem re. Parietalregion. Ein Ast der re. A. cerebri media war durch einen Riß der Dura ziehend zwischen Cortex und einer der Frakturlinien aufgespannt. Intracranielle Blutungen konnten ebenso wie Verletzungen der Arterie selbst nicht beobachtet werden. Der Fall ist erneut ein Indiz für die großen Relativbewegungen zwischen Gehirn und Schädel bei derartigen Traumen.
    Notizen: Summary A 63-year-old drunken man fell and hit his head on the ground. Apart from symptoms of alcoholisation no signs of severe injuries were found. The man died $$2{\raise0.5ex\hbox{$\scriptstyle 1$}\kern-0.1em/\kern-0.15em\lower0.25ex\hbox{$\scriptstyle 2$}}$$ days after the accident. The autopsy revealed a huge fracture system in the right parietal region. A branch of the medial cerebral artery was stretched between the cortex and one of the fracture lines, passing through a tear in the dura. Characteristics of this case were that no larger hemorrhage was found and the artery which was torn from the cortex showed no lesions. The case also indicates the immense relative movements between skull and brain which occur during such trauma.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 6
    Digitale Medien
    Digitale Medien
    Springer
    International journal of legal medicine 106 (1994), S. 274-276 
    ISSN: 1437-1596
    Schlagwort(e): Gas weapons ; Starter pistols ; Air embolism ; Gaswaffen ; Schreckschußwaffen ; Luftembolie
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Rechtswissenschaft
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Es wird über einen Suizid mit einer Gaspistole berichtet, die mit 8-mm-Platzpatronen geladen war. Der 58-jährige Mann hatte sich zunächst in die Schläfe und anschließend in den Nacken geschossen. Hierbei waren tiefreichende, beschmauchte Wundhöhlen entstanden. Die Weichteile waren alleine durch die explodierenden Gase geschädigt worden. Todesursache war eine Luft/Gasembolie.
    Notizen: Summary Case report on a suicide with a gas pistol loaded with 8 mm blank cartridges. A 58-year-old male shot himself in the right temple and then in the back of the neck. The contact shot wounds showed large wound cavities with interspersed powder particles. The soft tissues were injured solely by the pressure of the exploding powder. Death was due to an air/gas embolism in the right ventricle of the heart.
    Materialart: Digitale Medien
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